74268-mt----telecommunication Switching

NR

Code No: 74268/MT

M.Tech. – II Semester Regular Examinations, September, 2008 TELECOMMUNICATION SWITCHING (Electronics & Communications) Time: 3hours

1.a) b) 2.a) b)

Max. Marks:60

Answer any FIVE questions All questions carry equal marks --Explain the principle of operation of a cross bar switch. Compare blocking and non-blocking cross bar switches. Compare three modes of model of dual processor architecture with their merits and demerits. Derive the expression for unavailability of single processor and dual processor systems.

3.

What is Hybrid? Explain the operation of Echo suppressor with the help of neat sketch.

4.a) b)

Describe the architecture of SS7. Briefly explain the following terms (i) Grade of Service (ii) Blocking Probability

5.

Describe the operation of UART transmitter and receiver with the help of block diagram.

6.

What is the need for layered architecture? Explain the function of each layer in OSI-ISO reference model.

7.a) b)

Describe functional groupings and reference points of ISDN. Explain BISDN reference model.

8.a) b)

Describe SONET frame format and layers. Briefly explain about DOCSIS. &_&_&_&